By Doug Fraser
December 08, 2009 2:00 AM
WELLFLEET — Except for the occasional blink of an eye or turn of a head, it was hard to tell the living from the dead yesterday morning.
A total of 24 cold-stunned rare and endangered sea turtles were picked up off Cape Cod Bay beaches between Sunday afternoon and early yesterday morning, one of the largest single-day totals ever, according to Robert Prescott, director of the Massachusetts Audubon Society's Wellfleet Bay Wildlife Sanctuary.
Inside the sanctuary headquarters yesterday morning, staffer Michelle Stantial cleaned the turtles off, weighed and measured them, and prepared the survivors for shipping in cardboard crates lined with blankets to the New England Aquarium in Boston.
Five turtles were shipped on Sunday; of those, four died.
As of yesterday morning, four more endangered Kemp's ridley turtles had died at the sanctuary. The remaining 15, which were all ridleys except for one green sea turtle, were taken to the New England Aquarium for treatment and rehabilitation. At least two of those were dead on arrival, meaning their heartbeats were lower than one beat per minute.
The aquarium is currently treating 52 sea turtles — one loggerhead, four greens and 47 Kemp's ridleys, said spokesman Tony LaCasse.
"We knew it would be a big day," said Massachusetts Audubon naturalist Dennis Murley. "Those are some lucky turtles."
As a cold front bringing high winds swept over the Cape this weekend, Audubon sanctuary staff and trained volunteers marshaled people to walk night patrols from Dennis to Wellfleet. They were aided by volunteers during the day and received numerous tips from others walking the beaches, Murley said. Most of the turtles were found on Brewster beaches.
This year's balmy fall kept offshore water temperatures from dipping below 50 degrees until this weekend, Murley said.
Some sea turtles, which should have left the area for the 90-degree waters of the Gulf of Mexico long ago, have lingered too long, and were discovered only when they washed up onshore. Turtles are coldblooded, and while that means they require less food to survive than warmblooded animals, it also means their metabolism slows as water temperature cools. Land turtles burrow into mud to hibernate during cold months, but sea turtles must head for warmer waters.
At least one theory posits that warm offshore summer waters along the Outer Cape form a warm water "bridge" to the waters of Cape Cod Bay. With the onset of cold fall weather that link disappears, leaving turtles that remain in the bay disoriented about how to get back to the Atlantic and head south.
Murley pointed to one dead Kemp's ridley whose shell was heavily fouled with algae and other growth, indicating that it had been inactive for some time and may have tried to bury itself on the bottom to ride out cold water temperatures.
But ultimately a cold snap, with water dipping below 50 degrees, makes the turtles inactive; they float ashore with the prevailing winds.
Many had body temperatures as low as 30 and 40 degrees when found.
Green Sea Turtles
Can grow to 3 feet in length and weigh 350 pounds
Local population stretches from Texas to Massachusetts
Considered an endangered species worldwide
Adults eat sea grasses and algae
Kemp's Ridley sea turtles
Smallest sea turtle in world, averaging around 100 pounds and 2 feet in length
Eat mostly swimming crabs, but also jellyfish and mollusks
Range from Gulf of Mexico to New England
Endangered species in United States and worldwide